When performing power measurements, this is usually done in a test chamber. So as not to influence the measurement by stray emissions, the test chamber is insulated against electromagnetic radiation. One or more test antennas are usually placed within the test chamber and receive signals from a device under test, which is also placed in the test chamber. In order to evaluate the measured signals, they are usually guided to the outside of the test chamber through wave guides, for example coaxial cables. At the interface from the inside to the outside of the test chamber, there exists a possibility of stray electromagnetic radiation entering the test chamber and influencing the measurement.
For example the US patent application US 2016/0226607 A1 shows a measurement system having a number of measurement antennas. There, the individual measurement antenna transmits its measurement signal wirelessly to a receiver. This receiver though needs to be placed within a test chamber not disclosed in this document, since a transmission of signals to the outside is not possible due to the insulation against electromagnetic radiation. Having the receiver inside the test chamber though is also disadvantageous, since it takes up space within the test chamber and needs to operate without an interface of its own to the outside of the test chamber.
Accordingly, one object of the present invention among others is to provide a measuring device, measuring system and measuring method for performing over the air measurements, especially power measurements while requiring only a low-cost hardware set up but achieving a high measuring accuracy.